Re: [PATCH v6 2/3] Makefile: add Perl runtime prefix support

[Daniel Jacques <dnj@google.com>]

On Mon, Mar 19, 2018 at 3:21 PM Ævar Arnfjörð Bjarmason <avarab@gmail.com>
wrote:

> I think it would be more idiomatic and more paranoid (we'll catch bugs)
> to do:

>       my $exec_path;
>       if (exists $ENV{GIT_EXEC_PATH}) {
>           $exec_path = $ENV{GIT_EXEC_PATH};
>       } else {
>           [...]
>       }

> I.e. we're interested if we got passed GIT_EXEC_PATH, so let's see if it
> exists in the env hash, and then use it as-is. If we have some bug where
> it's an empty string we'd like to know, presumably...

Good idea, done.

> > +
> > +     # Trim off the relative gitexecdir path to get the system path.
> > +     (my $prefix = $exec_path) =~ s=${gitexecdir_relative}$==;

> The path could contain regex metacharacters, so let's quote those via:

>       (my $prefix = $exec_path) =~ s/\Q$gitexecdir_relative\E$//;

> This also nicely gets us rid of the more verbose ${} form, which makes
> esnse when we're doing ${foo}$ instead of the arguably less readbale
> $foo$, but when it's \Q$foo\E$ it's clear what's going on.

Ah cool - makes sense. I'm not strong with Perl, so I wasn't aware that
this was an option, but I agree it's cleaner. Done.